arch/riscv/kernel/setup.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
   4  *  Chen Liqin <liqin.chen@sunplusct.com>
   5  *  Lennox Wu <lennox.wu@sunplusct.com>
   6  * Copyright (C) 2012 Regents of the University of California
   7  * Copyright (C) 2020 FORTH-ICS/CARV
   8  *  Nick Kossifidis <mick@ics.forth.gr>
   9  */
  10
  11 #include <linux/acpi.h>
  12 #include <linux/cpu.h>
  13 #include <linux/init.h>
  14 #include <linux/mm.h>
  15 #include <linux/memblock.h>
  16 #include <linux/sched.h>
  17 #include <linux/console.h>
  18 #include <linux/of_fdt.h>
  19 #include <linux/sched/task.h>
  20 #include <linux/smp.h>
  21 #include <linux/efi.h>
  22 #include <linux/crash_dump.h>
  23 #include <linux/panic_notifier.h>
  24
  25 #include <asm/acpi.h>
  26 #include <asm/alternative.h>
  27 #include <asm/cacheflush.h>
  28 #include <asm/cpufeature.h>
  29 #include <asm/cpu_ops.h>
  30 #include <asm/early_ioremap.h>
  31 #include <asm/pgtable.h>
  32 #include <asm/setup.h>
  33 #include <asm/set_memory.h>
  34 #include <asm/sections.h>
  35 #include <asm/sbi.h>
  36 #include <asm/tlbflush.h>
  37 #include <asm/thread_info.h>
  38 #include <asm/kasan.h>
  39 #include <asm/efi.h>
  40
  41 #include "head.h"
  42
  43 /*
  44  * The lucky hart to first increment this variable will boot the other cores.
  45  * This is used before the kernel initializes the BSS so it can't be in the
  46  * BSS.
  47  */
  48 atomic_t hart_lottery __section(".sdata")
  49 #ifdef CONFIG_XIP_KERNEL
  50 = ATOMIC_INIT(0xC001BEEF)
  51 #endif
  52 ;
  53 unsigned long boot_cpu_hartid;
  54 static DEFINE_PER_CPU(struct cpu, cpu_devices);
  55
  56 /*
  57  * Place kernel memory regions on the resource tree so that
  58  * kexec-tools can retrieve them from /proc/iomem. While there
  59  * also add "System RAM" regions for compatibility with other
  60  * archs, and the rest of the known regions for completeness.
  61  */
  62 static struct resource kimage_res = { .name = "Kernel image", };
  63 static struct resource code_res = { .name = "Kernel code", };
  64 static struct resource data_res = { .name = "Kernel data", };
  65 static struct resource rodata_res = { .name = "Kernel rodata", };
  66 static struct resource bss_res = { .name = "Kernel bss", };
  67 #ifdef CONFIG_CRASH_DUMP
  68 static struct resource elfcorehdr_res = { .name = "ELF Core hdr", };
  69 #endif
  70
  71 static int __init add_resource(struct resource *parent,
  72                                 struct resource *res)
  73 {
  74         int ret = 0;
  75
  76         ret = insert_resource(parent, res);
  77         if (ret < 0) {
  78                 pr_err("Failed to add a %s resource at %llx\n",
  79                         res->name, (unsigned long long) res->start);
  80                 return ret;
  81         }
  82
  83         return 1;
  84 }
  85
  86 static int __init add_kernel_resources(void)
  87 {
  88         int ret = 0;
  89
  90         /*
  91          * The memory region of the kernel image is continuous and
  92          * was reserved on setup_bootmem, register it here as a
  93          * resource, with the various segments of the image as
  94          * child nodes.
  95          */
  96
  97         code_res.start = __pa_symbol(_text);
  98         code_res.end = __pa_symbol(_etext) - 1;
  99         code_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 100
 101         rodata_res.start = __pa_symbol(__start_rodata);
 102         rodata_res.end = __pa_symbol(__end_rodata) - 1;
 103         rodata_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 104
 105         data_res.start = __pa_symbol(_data);
 106         data_res.end = __pa_symbol(_edata) - 1;
 107         data_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 108
 109         bss_res.start = __pa_symbol(__bss_start);
 110         bss_res.end = __pa_symbol(__bss_stop) - 1;
 111         bss_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 112
 113         kimage_res.start = code_res.start;
 114         kimage_res.end = bss_res.end;
 115         kimage_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 116
 117         ret = add_resource(&iomem_resource, &kimage_res);
 118         if (ret < 0)
 119                 return ret;
 120
 121         ret = add_resource(&kimage_res, &code_res);
 122         if (ret < 0)
 123                 return ret;
 124
 125         ret = add_resource(&kimage_res, &rodata_res);
 126         if (ret < 0)
 127                 return ret;
 128
 129         ret = add_resource(&kimage_res, &data_res);
 130         if (ret < 0)
 131                 return ret;
 132
 133         ret = add_resource(&kimage_res, &bss_res);
 134
 135         return ret;
 136 }
 137
 138 static void __init init_resources(void)
 139 {
 140         struct memblock_region *region = NULL;
 141         struct resource *res = NULL;
 142         struct resource *mem_res = NULL;
 143         size_t mem_res_sz = 0;
 144         int num_resources = 0, res_idx = 0;
 145         int ret = 0;
 146
 147         /* + 1 as memblock_alloc() might increase memblock.reserved.cnt */
 148         num_resources = memblock.memory.cnt + memblock.reserved.cnt + 1;
 149         res_idx = num_resources - 1;
 150
 151         mem_res_sz = num_resources * sizeof(*mem_res);
 152         mem_res = memblock_alloc(mem_res_sz, SMP_CACHE_BYTES);
 153         if (!mem_res)
 154                 panic("%s: Failed to allocate %zu bytes\n", __func__, mem_res_sz);
 155
 156         /*
 157          * Start by adding the reserved regions, if they overlap
 158          * with /memory regions, insert_resource later on will take
 159          * care of it.
 160          */
 161         ret = add_kernel_resources();
 162         if (ret < 0)
 163                 goto error;
 164
 165 #ifdef CONFIG_CRASH_DUMP
 166         if (elfcorehdr_size > 0) {
 167                 elfcorehdr_res.start = elfcorehdr_addr;
 168                 elfcorehdr_res.end = elfcorehdr_addr + elfcorehdr_size - 1;
 169                 elfcorehdr_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 170                 add_resource(&iomem_resource, &elfcorehdr_res);
 171         }
 172 #endif
 173
 174         for_each_reserved_mem_region(region) {
 175                 res = &mem_res[res_idx--];
 176
 177                 res->name = "Reserved";
 178                 res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
 179                 res->start = __pfn_to_phys(memblock_region_reserved_base_pfn(region));
 180                 res->end = __pfn_to_phys(memblock_region_reserved_end_pfn(region)) - 1;
 181
 182                 /*
 183                  * Ignore any other reserved regions within
 184                  * system memory.
 185                  */
 186                 if (memblock_is_memory(res->start)) {
 187                         /* Re-use this pre-allocated resource */
 188                         res_idx++;
 189                         continue;
 190                 }
 191
 192                 ret = add_resource(&iomem_resource, res);
 193                 if (ret < 0)
 194                         goto error;
 195         }
 196
 197         /* Add /memory regions to the resource tree */
 198         for_each_mem_region(region) {
 199                 res = &mem_res[res_idx--];
 200
 201                 if (unlikely(memblock_is_nomap(region))) {
 202                         res->name = "Reserved";
 203                         res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
 204                 } else {
 205                         res->name = "System RAM";
 206                         res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 207                 }
 208
 209                 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
 210                 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
 211
 212                 ret = add_resource(&iomem_resource, res);
 213                 if (ret < 0)
 214                         goto error;
 215         }
 216
 217         /* Clean-up any unused pre-allocated resources */
 218         if (res_idx >= 0)
 219                 memblock_free(mem_res, (res_idx + 1) * sizeof(*mem_res));
 220         return;
 221
 222  error:
 223         /* Better an empty resource tree than an inconsistent one */
 224         release_child_resources(&iomem_resource);
 225         memblock_free(mem_res, mem_res_sz);
 226 }
 227
 228
 229 static void __init parse_dtb(void)
 230 {
 231         /* Early scan of device tree from init memory */
 232         if (early_init_dt_scan(dtb_early_va)) {
 233                 const char *name = of_flat_dt_get_machine_name();
 234
 235                 if (name) {
 236                         pr_info("Machine model: %s\n", name);
 237                         dump_stack_set_arch_desc("%s (DT)", name);
 238                 }
 239         } else {
 240                 pr_err("No DTB passed to the kernel\n");
 241         }
 242
 243 #ifdef CONFIG_CMDLINE_FORCE
 244         strscpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
 245         pr_info("Forcing kernel command line to: %s\n", boot_command_line);
 246 #endif
 247 }
 248
 249 extern void __init init_rt_signal_env(void);
 250
 251 void __init setup_arch(char **cmdline_p)
 252 {
 253         parse_dtb();
 254         setup_initial_init_mm(_stext, _etext, _edata, _end);
 255
 256         *cmdline_p = boot_command_line;
 257
 258         early_ioremap_setup();
 259         sbi_init();
 260         jump_label_init();
 261         parse_early_param();
 262
 263         efi_init();
 264         paging_init();
 265
 266         /* Parse the ACPI tables for possible boot-time configuration */
 267         acpi_boot_table_init();
 268
 269 #if IS_ENABLED(CONFIG_BUILTIN_DTB)
 270         unflatten_and_copy_device_tree();
 271 #else
 272         unflatten_device_tree();
 273 #endif
 274         misc_mem_init();
 275
 276         init_resources();
 277
 278 #ifdef CONFIG_KASAN
 279         kasan_init();
 280 #endif
 281
 282 #ifdef CONFIG_SMP
 283         setup_smp();
 284 #endif
 285
 286         if (!acpi_disabled)
 287                 acpi_init_rintc_map();
 288
 289         riscv_init_cbo_blocksizes();
 290         riscv_fill_hwcap();
 291         init_rt_signal_env();
 292         apply_boot_alternatives();
 293
 294         if (IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM) &&
 295             riscv_isa_extension_available(NULL, ZICBOM))
 296                 riscv_noncoherent_supported();
 297         riscv_set_dma_cache_alignment();
 298
 299         riscv_user_isa_enable();
 300 }
 301
 302 static int __init topology_init(void)
 303 {
 304         int i, ret;
 305
 306         for_each_possible_cpu(i) {
 307                 struct cpu *cpu = &per_cpu(cpu_devices, i);
 308
 309                 cpu->hotpluggable = cpu_has_hotplug(i);
 310                 ret = register_cpu(cpu, i);
 311                 if (unlikely(ret))
 312                         pr_warn("Warning: %s: register_cpu %d failed (%d)\n",
 313                                __func__, i, ret);
 314         }
 315
 316         return 0;
 317 }
 318 subsys_initcall(topology_init);
 319
 320 void free_initmem(void)
 321 {
 322         if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) {
 323                 set_kernel_memory(lm_alias(__init_begin), lm_alias(__init_end), set_memory_rw_nx);
 324                 if (IS_ENABLED(CONFIG_64BIT))
 325                         set_kernel_memory(__init_begin, __init_end, set_memory_nx);
 326         }
 327
 328         free_initmem_default(POISON_FREE_INITMEM);
 329 }
 330
 331 static int dump_kernel_offset(struct notifier_block *self,
 332                               unsigned long v, void *p)
 333 {
 334         pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",
 335                  kernel_map.virt_offset,
 336                  KERNEL_LINK_ADDR);
 337
 338         return 0;
 339 }
 340
 341 static struct notifier_block kernel_offset_notifier = {
 342         .notifier_call = dump_kernel_offset
 343 };
 344
 345 static int __init register_kernel_offset_dumper(void)
 346 {
 347         if (IS_ENABLED(CONFIG_RANDOMIZE_BASE))
 348                 atomic_notifier_chain_register(&panic_notifier_list,
 349                                                &kernel_offset_notifier);
 350
 351         return 0;
 352 }
 353 device_initcall(register_kernel_offset_dumper);